Literally this means to no longer have the ability to touch or feel with your fingers or hands. But to lose your touch actually means that you lose your ability or talent you once had when dealing with things, people or situations.
We use this when you’re usually good at a certain skill or talent, but then things start to go wrong.
“I don’t understand why none of the girls here want to speak to me.”
“It looks like you’ve lost your touch with the ladies.”
“Oh no, they used to love me, what happened?”